Water → HCID 89704786、化合物

To a solution of benzyl 5-benzyloxy-3,4-difluoro-2-((2-fluoro-phenyl)amino)benzoate (21.42 g, 46.26 mmol) in DMF (35 mL) was added NaN3 (3.61 g, 55.51 mmol). The mixture was stirred at 90° C. for 3 h. Then water (300 mL) was added. The solution was extracted with ethyl acetate (150 mL×3). The combined organic extracts were washed with water (100 mL×3) and brine (200 mL) sequentially, dried over Na2SO4 and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (petroleum ether/ethyl acetate, 10:1, v/v) and gave the desired product (white solid, 14.63 g, 65% yield). 1H NMR (400 MHz, CDCl3): δ 8.55 (s, 1H), 7.53 (dd, J=8.5, 2.1 Hz, 1H), 7.50-7.33 (m, 10H), 7.09 (m, 1H), 7.05 (m, 1H), 6.90 (m, 1H), 6.83 (m, 1H), 5.35 (s, 2H), 5.20 (s, 2H).